人口普查(20)

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

/**
 * 人口普查
 * 题目描述
 * 某城镇进行人口普查，得到了全体居民的生日。现请你写个程序，找出镇上最年长和最年轻的人。
 * 这里确保每个输入的日期都是合法的，但不一定是合理的——假设已知镇上没有超过200岁的老人，
 * 而今天是2014年9月6日，所以超过200岁的生日和未出生的生日都是不合理的，应该被过滤掉。
 * 输入描述:
 * 输入在第一行给出正整数N，取值在(0, 105]；随后N行，每行给出1个人的姓名（由不超过5个
 * 英文字母组成的字符串）、以及按“yyyy/mm/dd”（即年/月/日）格式给出的生日。题目保证最
 * 年长和最年轻的人没有并列。
 * 输出描述:
 * 在一行中顺序输出有效生日的个数、最年长人和最年轻人的姓名，其间以空格分隔。
 * 输入例子:
 * 5
 * John 2001/05/12
 * Tom 1814/09/06
 * Ann 2121/01/30
 * James 1814/09/05
 * Steve 1967/11/20
 * 输出例子:
 * 3 Tom John
 *
 * @author shijiacheng
 * @date 2018/2/1
 */
public class B1018Census {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        List<Person> list = new ArrayList<>();
        for (int i = 0; i < N; i++) {
            Person p = new Person();
            p.name = sc.next();
            p.setDateStr(sc.next());
            list.add(p);
        }

        int count = 0;
        int min = 0;
        int max = Integer.MAX_VALUE;
        String maxName = "";
        String minName = "";
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).date >= 18140906 && list.get(i).date <= 20140906) {
                count++;
                if (list.get(i).date < max) {
                    max = list.get(i).date;
                    maxName = list.get(i).name;
                }

                if (list.get(i).date > min) {
                    min = list.get(i).date;
                    minName = list.get(i).name;
                }
            }

        }
        System.out.println(count + " " + maxName + " " + minName);
    }

    static class Person {
        String name;
        int date;
        String dateStr;

        public void setDateStr(String dateStr) {
            this.dateStr = dateStr;
            String[] str = dateStr.split("/");
            this.date = Integer.parseInt(str[0]) * 10000
                    + Integer.parseInt(str[1]) * 100 + Integer.parseInt(str[2]);
        }
    }
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class Main {

	public static class Person implements Comparable<Person> {
	
		String name;
		String birthday;

		public Person(String name, String birthday) {
			this.name = name;
			this.birthday = birthday;
		}

		public int compareTo(Person o){ 
			return  this.birthday.compareTo(o.birthday);
		}
	}

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		ArrayList<Person> person = new ArrayList<>();
		for (int i = 0; i < n; i++) {
			Person p = new Person(in.next(), in.next());
			person.add(p);
		}
		Collections.sort(person);
		Person p1 = new Person("tom","2014/09/06");
		Person p2 = new Person("tom","1814/09/06");
		int count = 0;
		boolean flag1 = true;
		String[] name = new String[2];
		for (Person p : person) {
			if (p.compareTo(p2) >= 0 && p.compareTo(p1) <= 0) {
				count++;
			}
			if (p.compareTo(p2) >= 0 && flag1) {
				name[0] = p.name;
				flag1 = false;
			}
			if (p.compareTo(p1) <= 0) {
				name[1] = p.name;
			}
		}
		System.out.printf("%d %s %s", count, name[0], name[1]);
	}
}

#include<stdio.h>
#include<string.h>
int main (){//the shorter,the better.
    int n,i,cnt;char b[11],max[11]="1814/09/06",min[11]="2014/09/06",t[6],o[6],y[6]; 
    for(;~scanf("%d",&n);printf("%d %s %s\n",cnt,y,o))
       for (cnt=i=0; i < n&&~scanf("%s %s",t,b);strcmp(b,"1814/09/06")<0||strcmp(b,"2014/09/06")>0?:(strcmp(max,b)>0?:(strcpy(max,b),strcpy(o,t),1),strcmp(min,b)<0?:(strcpy(min,b),strcpy(y,t),1),++cnt),i++);
}

#include<iostream>
#include<algorithm>
using namespace std;
const int maxn = 100010;
struct Per{
	char name[5];
	int year, month, day;
	int rank;
}per[maxn];
bool judge(Per a){
	if (a.year>2014 || a.year<1814)
		return false;
	else if (a.year == 2014 && a.month>9 || a.year == 1814 && a.month<9)
		return false;
	else if (a.year == 2014 && a.month == 9 && a.day>6 || a.year == 1814 && a.month == 9 && a.day<6)
		return false;
	else return true;
}
bool cmp(Per a, Per b){
	if (a.rank != b.rank)return a.rank > b.rank;
	if (a.year != b.year)
		return a.year>b.year;
	else if (a.month != b.month)
		return a.month>b.month;
	else return a.day>b.day;
}
int main(){
	int n;
	cin >> n;
	int cnt = 0;
	for (int i = 0; i<n; i++){
		cin >> per[i].name;
		scanf_s("%d/%d/%d", &per[i].year, &per[i].month, &per[i].day);
		if (judge(per[i])){
			cnt++;
			per[i].rank = 1;
		}
		else
			per[i].rank = 0;
	}
	cout << cnt << " ";
	sort(per, per + n, cmp);
	cout << per[cnt - 1].name<<" " << per[0].name;
}

思路

1. 年月日比较法，按顺序依次比较年月日，封装成函数。

2. 利用字符串的顺序比较，借助STL的string直接比较得出结果，不需要封装函数。

方法一

注意：结果为0时，只需要输出0，而不需要其他，包括空格。

年月日依次比较

/*
 * app=PAT-Basic lang=c++
 * https://pintia.cn/problem-sets/994805260223102976/problems/994805293282607104
 */
#include <cstdio>
#include <cstring>
using namespace std;
const int maxn = 100010;
struct person{
    char name[6];
    int year;
    int month;
    int day;
}temP,maxP,minP,max,min;
/* 
 * 年份，月份，天均小于等于 --- 年龄大于等于
 */
bool lessEqu(person p1,person p2){
    if (p1.year != p2.year)
        return p1.year <= p2.year;
    if (p1.month != p2.month)
        return p1.month <= p2.month;
    else
        return p1.day <= p2.day;
}
/* 
 * 年份，月份，天均大于等于 --- 年龄小于等于
 */
bool moreEqu(person p1, person p2){
    if (p1.year != p2.year)
        return p1.year >= p2.year;
    if (p1.month != p2.month)
        return p1.month >= p2.month;
    else
        return p1.day >= p2.day;
}
void init(){
    minP.year = min.year = 1814;
    maxP.year = max.year = 2014;
    maxP.month = minP.month = max.month = min.month = 9;
    maxP.day = minP.day = max.day = min.day = 6;
}
int main()
{
    int n;
    int year, month, day;
    init();
    scanf("%d",&n);
    int count = 0;
    for (int i = 0; i < n; i++){
        scanf("%s %d/%d/%d", temP.name, &temP.year, &temP.month, &temP.day);
        if (lessEqu(temP, max) && moreEqu(temP, min)){
            count++;
            if (lessEqu(temP, maxP)){
                maxP = temP;
            }
            if (moreEqu(temP, minP)){
                minP = temP;
            }
        }
    }
    printf("%d",count);
    if (count!=0)
        printf(" %s %s", maxP.name, minP.name);
    return 0;
}

方法二

直接利用STL:string比较。不需要自封装比较函数，但是不熟悉string方法的，需要知道string的比较判断，是按照字符顺序的ascii码比较，所以可以用string的直接比较来解决。

/*
 * app=PAT-Basic lang=c++
 * https://pintia.cn/problem-sets/994805260223102976/problems/994805293282607104
 */
#include <cstdio>
#include <string>
#include <iostream>
using namespace std;
int main(){
    int n;
    scanf("%d",&n);
    int count = 0;
    string s1, s2, left = "1814/09/06", right = "2014/09/06";
    string max = right, min = left, maxName, minName;
    for (int i = 0; i < n; i++){
        cin >> s1 >> s2;
        if (s2 >= left && s2 <= right){
            count++;
            if (s2 < max){
                max = s2;
                maxName = s1;
            }
            if (s2 >min){
                min = s2;
                minName = s1;
            }
        }
    }
    cout << count;
    if (count != 0)
        cout << " " << maxName << " " << minName << endl;
    return 0;
}

PAT、牛客网通过代码

#include<iostream>
using namespace std;
int main(){
    int N;
    int birth;
    string date;
    string name;
    int max=18140906,min=20140906;
    int maxIndex,minIndex;
    string maxName,minName; 
    cin>>N;
    int qualifiedNum=N;
    if(N>0){//没有这步判断 测试点3段错误 
        for(int i=0;i<N;i++){
            cin>>name>>date;
            birth=stoi(date.substr(0,4))*10000+stoi(date.substr(5,2))*100+stoi(date.substr(8,2));
            //谁的出生日期的整数值，小的最小，大的最大 
            if(birth>20140906||birth<18140906){//不在合法范围 
                //birth=0;//不合法生日置零 
                qualifiedNum--;//合法数字-- 
            }else{//在合法范围 
                if(max<birth){//最大值 
                    max=birth;
                    maxIndex=i;
                    maxName=name;
                }
                if(min>birth){//最小值 
                    min=birth;
                    minIndex=i;
                    minName=name;
                }    
            }
        } 
        if(qualifiedNum==0){//如果所有数据都不合法 输出0，否则测试点3格式错误 
            cout<<"0";
            return 0;
        }
        cout<<qualifiedNum<<" "<<minName<<" "<<maxName;
    } 
    return 0;
}

#include <iostream>
#include <string>
//#include<string.h>
#include<list>
using namespace std;

string String2int(string it)
{     string sub;     int i = it.find(" ", 0);     sub = it.substr(i + 1, it.size() - i - 1);     int j = sub.find_first_of("/", 0);     sub.erase(j, 1);     int z = sub.find("/", 0);     sub.erase(z, 1);     return sub;
}

int  main()
{     int N;     cin >> N;     cin.get();     list<string> str;     while (N>0)     {         string tmp;         getline(cin, tmp);         str.push_back(tmp);         N--;     }     for (list<string>::iterator it = str.begin();it != str.end();)     {         string sub = String2int(*it);         if (stoi(sub)>20140906||stoi(sub)<18140906)         {             str.erase(it++);         }         else         {             it++;         }     }     cout << str.size();     string max, min;     //max = min = "20140906";     bool flag = false;     for (list<string>::iterator it = str.begin();it != str.end();it++)     {         string sub = String2int(*it);         if (!flag) {             min = max = sub;             flag = true;         }                      else         {             //max = min = sub;             if (stoi(max)>stoi(sub))             {                 max = sub;             }             else if (stoi(min)<stoi(sub))             {                 min = sub;             }         }              }     //bool tag = false;     for (list<string>::iterator it = str.begin();it != str.end();it++)     {         string sub = String2int(*it);         int i = it->find(" ", 0);         if (stoi(max)==stoi(sub))         {             cout <<" "<< it->substr(0, i);         }     }     for (list<string>::iterator it = str.begin();it != str.end();it++)     {         string sub = String2int(*it);         int i = it->find(" ", 0);         if (stoi(min) == stoi(sub))         {             cout << " " << it->substr(0, i);         }     }     cout << endl;     system("pause");     return 0;
}

#在输入的过程中进行查找，不用保存下来。节省空间
try:
    while True:
        num = int(input())
        pastDays = '1814/09/06'    #初始化最早的出生日期
        nowDays = '2014/09/06'     #最晚的生日
        young = '1814/09/06'       #初始化年轻人的生日为最老
        elder = '2014/09/06'       #初始化老年人的生日为最年轻
        legal = 0
        for i in range(num):       #输入中比较
            temp = input().split() 
            if pastDays <= temp[1] <= nowDays:
                legal += 1
                if temp[1] > young:
                    youngName = temp[0]
                    young = temp[1]
                if temp[1] < elder:
                    elder = temp[1]
                    elderName = temp[0]
        print("%d %s %s" % (legal,elderName,youngName))
except Exception:
    pass

#include <iostream>
#include<string>
#include<vector>
#include<algorithm>
using namespace std;
typedef struct node
{
	string name;
	string date;
	int age;
	bool test()
	{
		bool sta;
		int sum = 0, t;
		for (auto c : date)
		{
			if (c >= '0'&&c <= '9')
				sum = sum * 10 + c - '0';		
		}
		age = sum;
		if (20140906 - sum <= 2000000 && sum < 20140906)
			sta = true;
		else
			sta = false;
		return sta;
	}
}node;
bool cmp(const node& x, const node& y)
{
	return x.age < y.age;
}
int main()
{		
	int length;
	while (cin >> length)
	{
		node n;
		vector<node> data;
		for (int i = 0; i < length; i++)
		{
			cin >> n.name >> n.date;
			if (n.test() == true)
				data.push_back(n);
		}
		sort(data.begin(), data.end(), cmp);
		cout << data.size() << " " << data[0].name << " " << data[data.size() - 1].name << endl;
	}
	return 0;
}

	#include<iostream>



	#include<string.h>



	using namespace std;



	 



	// PAT乙级人口普查(20)



	bool timeCompare(chartime1[11],chartime2[11]);



	intmain()



	{



	    intN,i,cnt=0;



	    cin>>N;



	    charnames[10],OldName[10],YoungName[10];



	    chartimes[11],OldTime[11]="1814/09/05",YoungTime[11]="2015/09/07";



	    charStartTime[11]="1814/09/05",FinishTime[11]="2015/09/07";



	    for(i=0;i<N;i++){



	        cin>>names>>times;



	        if((timeCompare(times,StartTime)) &&(timeCompare(FinishTime,times))){



	            cnt++;



	            //find the oldest one



	            if(timeCompare(YoungTime,times)){



	                strcpy(YoungTime,times);



	                strcpy(OldName,names);



	            }



	            //find the youngest one



	            if(timeCompare(times,OldTime)){



	                strcpy(OldTime,times);



	                strcpy(YoungName,names);



	            }



	        }



	    }



	    if(cnt>0)



	        cout<<cnt<<" "<<OldName<<" "<<YoungName<<endl;



	    else



	        cout<<"0";



	    return0;



	}



	//compare the times



	bool timeCompare(chartime1[11],chartime2[11])



	{



	    //time1 > time2 return true;



	    inti;



	    for(i=0;i<10;i++){



	        if(time1[i] - time2[i] > 0)



	            returntrue;



	        if(time1[i] - time2[i] < 0)



	            returnfalse;



	    }



	    returnfalse;



	}

import java.util.Scanner;
public class Main {
	private static final int TODAY = 20140906;
	private static final int LIMIT = 18140906;
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int max = Integer.MIN_VALUE;
		int min = Integer.MAX_VALUE;
		String eldest = null;
		String youngest = null;
		int count = 0;
		while(--n>=0){
			String name = in.next();
			String date = in.next();
			String[] d = date.split("/");
			int time = Integer.parseInt(d[0]);
			time = time*100+(d[1].charAt(0)-'0')*10+(d[1].charAt(1)-'0');
			time = time*100+(d[2].charAt(0)-'0')*10+(d[2].charAt(1)-'0');
			if(time>TODAY)
				continue;
			if(time<LIMIT)
				continue;
			count++;
			if(time>max){
				max = time;
				youngest = name;
			}
			if(time<min){
				min = time;
				eldest = name;
			}
		}
		System.out.println(count+" "+eldest+" "+youngest);
	}
}

#include<iostream>
#include<string>
#include<algorithm>
using namespace std;
struct people {
	string name;
	int y, m, d;
	bool operator <(const people& l)const
	{
		if (y<l.y)
			return true;
		if (y == l.y)
		{
			if (m<l.m)
				return true;
			if (m == l.m)
				return d<l.d;
			return false;
		}
		return false;
	}
};
people a[100005];
int main()
{
	int n, i = 0, y, m, d;
	string name, tmp, tmp1, tmp2, tmp3;
	cin >> n;
	while (n--)
	{
		cin >> name >> tmp;
		tmp1 = tmp.substr(0, 4);
		tmp2 = tmp.substr(5, 2);
		tmp3 = tmp.substr(8, 2);
		y = (tmp1[0] - '0') * 1000 + (tmp1[1] - '0') * 100 + (tmp1[2] - '0') * 10 + tmp1[3] - '0';
		m = (tmp2[0] - '0') * 10 + tmp2[1] - '0';
		d = (tmp3[0] - '0') * 10 + tmp3[1] - '0';
		if (y > 2014 || y < 1814)
			continue;
		else if (y == 2014 || y == 1814)
		{
			if (y == 2014)
			{
				if (m > 9)
					continue;
				else if (m == 9)
				{
					if (d > 6)
						continue;
				}
			}
			else
			{
				if (m < 9)
					continue;
				else if (m == 9)
				{
					if (d < 6)
						continue;
				}
			}
		}
		a[i].y = y;
		a[i].m = m;
		a[i].d = d;
		a[i].name = name;
		i++;
	}
	sort(a, a + i);
	cout << i << " " << a[0].name << " " << a[i - 1].name;
	return 0;
}

#include<iostream>
#include<cmath>
#include<cstdio>
#include<cstring>
using namespace std;

int main()
{
	int n,cnt=0,max_i=-1,min_i=-1;
	cin>>n;
	string name[100000],birthday[100000];
	string oldday="2014/09/06",youngday="1814/09/06";
//和总是把max初始化为最小道理一样 
	for(int i=0;i<n;i++)
	{
		cin>>name[i]>>birthday[i];
		
		if(birthday[i]>="1814/09/06" && birthday[i]<="2014/09/06")
		{
				cnt++;	
			if(birthday[i]>=youngday)//在合法的情况下查找最大和最小 
			{
				youngday=birthday[i];
				min_i=i;
			}
			if(birthday[i]<=oldday)
			{
				oldday=birthday[i];
				max_i=i;
			}	
		}
	 } 
	
	 if(cnt>0)
		{
			cout<<cnt<<" ";
			cout<<name[max_i]<<" "<<name[min_i];
		 } 
	else
		 cout<<"0";
	return 0;
}

#include <iostream>

using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    int N; cin >> N;
    string name, str;
    string minStr="z", minName="";
    string maxStr="", maxName="";
    string start = "1814/09/06";
    string end = "2014/09/06";
    int counts = 0;
    for(int i=0; i<N; i++) {
        cin >> name >> str;
        if(str>=start && str<=end) {
            counts++;
            if(minStr > str) {
                minStr = str;
                minName = name;
            }
            if(maxStr < str) {
                maxStr = str;
                maxName = name;
            }
        }
    }
    cout << counts << " " << minName << " " << maxName << endl;
    return 0;
}

#include <iostream>